Recently, biodiesel has gained significant attention as it is a renewable, biodegradable, less pollutant emitting, non-toxic and more environmentally friendly fuel source as compared with the fossil diesel fuel available at present. Biodiesel can be used as a substitute for petrochemical diesel by blending with petrochemical diesel. In the past 10 years, global biodiesel market emerged stabile growth of biodiesel production. The raw materials for biodiesel production account for almost 60～80% of the total biodiesel cost. Therefore, a number of research projects have been carried out using non-edible oils such as Jatropha oil or fats, and other waste oils, to reduce the raw material cost.
Prof. Fang Zhen of Xishuangbanna Tropical Botanical Garden (XTBG) and his research team prepared a solid acid catalyst from Kraft lignin by treatment with phosphoric acid, pyrolysis and sulfuric acid. Subsequently, they used it as catalyst to synthesize biodiesel from high-acid value Jatropha oil.
In the biodiesel production process with the catalyst, first, the esterification of oleic acid was studied with an orthogonal experimental design to optimize reaction variables. Various reaction parameters, such as catalyst loading, reaction temperature and oil-to-methanol ratio on the esterification rate were optimized.
In the study, the highest catalytic activity was achieved with a 96.1% esterification rate, and the catalyst can be reused three times with little deactivation under optimized conditions. Biodiesel production from Jatropha oil was studied under such conditions. It was found that 96.3% biodiesel yield from non-pretreated Jatropha oil with high-acid value (12.7 mg KOH/g) could be achieved.
The researchers thus proposed that the single-step process could be a potential route for biodiesel production from high-acid value oil by simplifying the procedure and reducing costs.
The study entitled “Direct production of biodiesel from high-acid value Jatropha oil with solid acid catalyst derived from lignin” has been published online in Biotechnology for Biofuels, 2011, 4:56 doi:10.1186/1754-6834-4-56.
Moreover, a monograph named Biodiesel: Blends, Properties and Applications has been published by NOVA Publishers. The monograph was co-edited by Jorge Mario Marchetti andFANG Zhen.